sinqmi
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NAME
SINQMI - initialization routine for SINQMB and SINQMF
SYNOPSIS
SUBROUTINE SINQMI (N, WSAVE, LENSAV, IER)
INTEGER N, LENSAV, IER
REAL WSAVE(LENSAV)
DESCRIPTION
FFTPACK 5.0 subroutine SINQMI initializes array WSAVE for use
in its companion routines SINQMF and SINQMB. The prime factor-
ization of N together with a tabulation of the trigonometric
functions are computed and stored in array WSAVE. Separate
WSAVE arrays are required for different values of N.
Input Arguments
N Integer length of each sequence to be transformed. The
transform is most efficient when N is a product of
small primes.
LENSAV Integer dimension of WSAVE array. LENSAV must be at least
2*N + INT(LOG (REAL(N))) +4.
Output Arguments
WSAVE Real work array with dimension LENSAV, containing the
prime factors of N and also containing certain trigonometric
values which will be used in routines SINQMB or SINQMF.
IER Integer error return
= 0 successful exit
= 2 input parameter LENSAV not big enough
= 20 input error returned by lower level routine